Use Blocks from Block Sync in Block Manager (cosmos#1056)

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## Overview
Resolves: cosmos#1053, resolves: cosmos#1060, resolve cosmos#1061

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---------

Co-authored-by: Ganesha Upadhyaya <[email protected]>

block/block_cache.go

@@ -0,0 +1,60 @@
+package block
+
+import (
+	"sync"
+
+	"github.com/rollkit/rollkit/types"
+)
+
+type BlockCache struct {
+	blocks            map[uint64]*types.Block
+	hashes            map[string]bool
+	hardConfirmations map[string]bool
+	mtx               *sync.RWMutex
+}
+
+func NewBlockCache() *BlockCache {
+	return &BlockCache{
+		blocks:            make(map[uint64]*types.Block),
+		hashes:            make(map[string]bool),
+		hardConfirmations: make(map[string]bool),
+		mtx:               new(sync.RWMutex),
+	}
+}
+
+func (bc *BlockCache) getBlock(height uint64) (*types.Block, bool) {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	block, ok := bc.blocks[height]
+	return block, ok
+}
+
+func (bc *BlockCache) setBlock(height uint64, block *types.Block) {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	bc.blocks[height] = block
+}
+
+func (bc *BlockCache) deleteBlock(height uint64) {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	delete(bc.blocks, height)
+}
+
+func (bc *BlockCache) isSeen(hash string) bool {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	return bc.hashes[hash]
+}
+
+func (bc *BlockCache) setSeen(hash string) {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	bc.hashes[hash] = true
+}
+
+func (bc *BlockCache) setHardConfirmed(hash string) {
+	bc.mtx.Lock()
+	defer bc.mtx.Unlock()
+	bc.hardConfirmations[hash] = true
+}